Characterisation and feasibility as carbon fibre precursors of isotropic pitches derived from anthracene oil

Abstract

This work describes the preparation of isotropic carbon fibres from three anthracene oil-derived pitches of different softening points. The total absence of solid particles (e.g., primary quinoline insoluble (QI) particles) and the high aromatic composition turn these precursors into a promising raw material for the preparation carbon fibres, as they can be used without any pre-treatment. The carbon fibres were prepared by a melting process that involved the spinning of the pitches and subsequent oxidative stabilization with air and carbonisation. Scanning electron microscopy was used to monitor the surface appearance and diameter of the fibres.The results showed that softening point by itself cannot explain the spinning behaviour of the pitches. Therefore, detailed characterisation of the samples by means of size exclusion chromatography, UV–fluorescence spectroscopy, and laser desorption time-of-flight mass spectrometry was used to elucidate the composition of the pitches, especially their molecular weight distributions. The combination of the characterisation of the precursors with the characterisation of the fibres provides an overall vision of the carbon fibre preparation from the pitches and will certainly permit a pre-selection of the most appropriate precursor for this application.